Delabie E, Jaspers R J E, von Hellermann M G, Nielsen S K, Marchuk O
FOM-Rijnhuizen, EURATOM-FOM, NL-3430 BE Nieuwegein, The Netherlands.
Rev Sci Instrum. 2008 Oct;79(10):10E522. doi: 10.1063/1.2955575.
An upgraded charge exchange spectroscopy diagnostic has been taken into operation at the TEXTOR tokamak. The angles of the viewing lines with the toroidal magnetic field are close to the pitch angles at birth of fast ions injected by one of the neutral beam injectors. Using another neutral beam for active spectroscopy, injected counter the direction in which fast ions injected by the first beam are circulating, we can simultaneously measure a fast ion tail on the blue wing of the D(alpha) spectrum while the beam emission spectrum is Doppler shifted to the red wing. An analysis combining the two parts of the spectrum offers possibilities to improve the accuracy of the absolute (fast) ion density profiles. Fast beam modulation or passive viewing lines cannot be used for background subtraction on this diagnostic setup and therefore the background has to be modeled and fitted to the data together with a spectral model for the slowing down feature. The analysis of the fast ion D(alpha) spectrum obtained with the new diagnostic is discussed.
一种升级后的电荷交换光谱诊断设备已在TEXTOR托卡马克装置上投入运行。观测线与环形磁场的夹角接近其中一个中性束注入器注入的快离子产生时的螺距角。使用另一束中性束进行有源光谱分析，该中性束的注入方向与第一束注入的快离子的循环方向相反，我们可以在D（α）光谱的蓝翼上同时测量快离子尾部，而束发射光谱则发生多普勒频移至红翼。对光谱的这两部分进行联合分析，为提高绝对（快）离子密度分布的精度提供了可能。在这种诊断设置中，不能使用快束调制或无源观测线进行背景扣除，因此必须对背景进行建模，并将其与用于慢化特征的光谱模型一起拟合到数据中。本文讨论了用新诊断设备获得的快离子D（α）光谱的分析结果。
